Pen cap



FIG. 1 is an upper front left perspective view of a pen cap showing mynew design;

FIG. 2 is a front elevation view thereof, with the rear elevation viewbeing a mirror image of the front elevation view;

FIG. 3 is a right side elevation view thereof, with the left sideelevation view being a mirror image of the right side elevation view;

FIG. 4 is a top plan view thereof; and,

FIG. 5 is a bottom plan view thereof.

The broken lines in FIG. 5 that define the bounds of the claimed designform no part thereof.

CLAIM The ornamental design for a pen cap, as shown and described.